Vacuum cleaner having a noise blocking member facing an intake vent of a motor fan

ABSTRACT

In an electric vacuum cleaner having an intake air opening  18  disposed in a front portion of a main body case  17 , a dust collection case  19  which communicates with the intake air opening  18 , and a motor fan  20  provided in a back portion of the main body case, and an intake air passage  23, 24, 25  from the dust collection case  19  to the motor fan  20  being formed, a noise blocking member  14   d  having a specific gravity larger than a material composing the main body case  17  and an area wider than a project area of an intake vent  20   a  is disposed in the intake air passage  25  facing to the intake vent  20   a  of the motor fan  20.

This application is a U.S. National Phase Application under 35 USC 371of International Application PCT/JP03/09391 filed Jul. 24, 2003.

TECHNICAL FIELD

The present invention relates to an electric vacuum cleaner including adust separation section, a motor fan, and an intake air passage which isprovided from the dust separation section to the motor fan.

BACKGROUND ART

There has been known a conventional electric vacuum cleaner whichgenerates negative pressure by driving a motor fan and sucks dust andthe like to be collected by the negative pressure.

A motor fan is generally disposed in a back part of a main body casewhich constitutes an outer wall of a cleaner main body, and an intakevent of its motor fan is directed forward. Collection members such as adust collection filter and a dust collection case are disposed ahead ofthe motor fan, and the electric vacuum cleaner is constructed in orderfor the dust to be collected in the dust collection case whileintroducing the negative pressure into the dust collection case by themotor fan.

However, for the above electric vacuum cleaner, there has been a problemthat the undesired sound generated by the rotation of the motor fan isvery noisy.

It is, therefore, an object of the present invention to provide anelectric vacuum cleaner capable of reducing the noise generated byrotation of a fan.

DISCLOSURE OF INVENTION

According to one aspect of the invention, an electric vacuum cleanerincludes an intake air opening disposed in a front portion of main bodycase, a dust separation section which communicates with the intake airopening, and a motor fan provided in a back portion of the main bodycase. In addition, an intake air passage is provided from the dustseparation section to the motor fan. Moreover, according to this aspectof the invention, a noise blocking member faces an intake vent of themotor fan with the intake air passage provided between the noiseblocking member and the intake vent. The noise blocking member has aspecific gravity that is larger than a specific gravity of a materialcomposing the main body case. And a surface of the noise blocking memberthat faces the intake vent has an area that is larger than a projectarea of the intake vent, which is an area of the intake vent projectedalong a central axis of the intake vent on the surface of the noiseblocking member.

According to another aspect of the invention, an electric vacuum cleanerincludes an intake air opening disposed in a front portion of a mainbody case, a dust separation portion which communicates with the intakeair opening, and a motor fan provided in a back portion of the main bodycase. In addition, intake air passage is provided from the dustseparation section to the motor fan. Moreover, according to this aspectof the invention, a battery faces an intake vent of the motor fan via awall of the intake air passage such that the intake air passage isprovided between the noise blocking member and the intake vent. Thebattery has a specific gravity that is larger than a specific gravity ofa material composing the main body case. And a surface of the batterythat faces the intake vent has an area that is larger than a projectarea of the intake vent, which is an area of the intake vent projectedalong a central axis of the intake vent on the surface of the battery.

According to a further aspect of the invention, an electric vacuumcleaner includes an intake air opening disposed in a front portion of amain body case, a dust separation section which communicates with theintake air opening, and a motor fan provided in a back portion of themain body case. In addition, an intake air passage is provided from thedust separation section to the motor fan. Moreover, according to thisaspect of the invention, the motor fan is tilted downwardly so that anintake vent of the motor fan is directed obliquely forward toward thefront portion of the main body case and obliquely downward. And abattery, for driving the motor fan, is positioned under a bottom wall ofa bottom portion of the intake air passage, wherein the bottom wallfaces the intake vent.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a longitudinal section view illustrating an electric vacuumcleaner main body according to an embodiment of the present invention.

FIG. 2 is a perspective view illustrating an electric vacuum cleaneraccording to the present invention.

FIG. 3 is an explanatory view illustrating the electric vacuum cleaneraccording to the second embodiment.

FIG. 4 is an explanatory view illustrating the electric vacuum cleaneraccording to the third embodiment.

FIG. 5 is an explanatory view illustrating a lower case.

FIG. 6 is an explanatory view illustrating a projection plane of anintake vent of a motor fan.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of an electric vacuum cleaner according to thepresent invention will be described according to the drawings.

In FIG. 2, reference character 1 denotes an electric vacuum cleaner mainbody (electric vacuum cleaner), reference character 2 a bellows-typedhose attachably and detachably connected ahead of the electric vacuumcleaner main body 1, reference character 3 a hand operating pipeprovided with the leading end of the hose 2, reference character 4 aretractable extension pipe attachably and detachably connected to thehand operating pipe, and reference character 5 is a suction opening bodyattachably and detachably connected to the leading end of the extensionpipe 4.

The electric vacuum cleaner 1 is provided with a main body case 17 whichis made of a resin lower case 13 having a turning wheel 11 as a frontwheel and a rear wheel 12, a resin upper case 14 disposed on the lowercase 13, and a resin upper cover 16 having a carrying handle 16 aopenably and closeably attached to the upper case 14 through a hinge 15.An intake air opening 18 is formed in the front potion of the electricvacuum cleaner main body 1 by a part of the upper cover 16; the hose 2is attachably and detachably connected to the intake air opening 18.

Further, in the front portion of the electric vacuum cleaner main body1, a flat mounting portion 14 a is formed below the intake air opening18 by a part of the upper case 14, and a cup like dust collection case19 is attachably and detachably mounted on the mounting portion 14 a. Amotor fan 20 is disposed in the back portion of the electric vacuumcleaner main body 1. The motor fan 20 is diagonally disposed in orderfor an intake vent 20 a to be faced downward and frontward. A battery(noise blocking member: battery unit) 21 for driving the motor fan 20 isdisposed below the motor fan 20.

The battery 21 consists of a storage battery, but it may be a batteryunit which is made of a plurality of secondary cells and a coverbundling the plurality of secondary cells. The battery 21 is placedfacing to the intake vent 20 a of the electric fan 20 through anafter-mentioned lateral wall (bottom wall portion) 14 d. Namely, thebattery 21 is disposed facing to the intake vent 20 a of the motor fan20.

Further, as shown in FIG. 6, an upper surface 21 k of the battery 21 andthe lateral wall 14 d have areas larger than project areas Sa, Sb whenthe intake vent 20 a of the motor fan 20 is projected on the uppersurface 21 k along the direction of the central axis line L of theintake vent 20 a. The specific gravity of the battery (battery mainbody) 21 is larger than the specific gravity of resin composing the mainbody case 17.

The lower case 13 is provided with a storage space 13 b. A storageopening 13 a for conducing the exchange of the battery 21, and the likeis formed in the bottom surface of the storage space 13 b. The storageopening 13 a can open and close by the battery cover 22. As shown inFIG. 5, the upper surface of the lower case 13 is provided with anopening 13 c, and a storage wall 13 d of an upper wall is integrallyformed thereto. The corner between the back surface and the bottomsurface of the lower case 13 is formed with a concave portion 13 e forcharging in which a contact point (not shown) of a battery charge (notshown) capable of charging with storing the battery 21 is placed.

A first intake air passage 23 for communicating with an upper partopening 19 a of the dust collection case 19 is formed on the upper cover16.

The main body case 17 having an opening 24 a on the upper surface isprovided with a second intake air passage 24 extending up and down and athird intake air passage 25 for communicating with the second intake airpassage 24 and also the intake vent 20 a of the motor fan 20. The firstintake air passage 23 of the upper cover 16 is communicated with theopening 24 a of the second intake air passage 24, and a filter 26 isdisposed thereto. The second intake air passage 24 is zoned bylongitudinal walls 14 b, 14 c, and the like integrally formed to theupper case 14. The third intake air passage 25 is zoned by a lateralwall 14 d, and the like integrally formed to the upper case 14. Thebottom portion of the third intake air passage 25 is zoned by thelateral wall 14 d. A part of the lateral wall 14 d closes the opening 13c of the lower case as shown in FIG. 5, and comes into contact with theouter surface (upper surface) 21 k of the battery 21.

The motor fan 20 is covered with a motor fan cover 27 having an opening27 a, and its vibration is absorbed by a rubber vibration isolation 28.

Next, an operation of the electric vacuum cleaner according to the aboveembodiment will be described. When the motor fan 20 is driven, thesecond and the first intake air passages 25, 24 become negative pressurestates, and then the dust collection case 19 becomes under negativepressure through the first intake air passage 23 of the upper cover 16and the upper side opening 19 a of the dust collection case 19. Withthis negative pressure, dust is sucked from the suction opening body 5together with air, and the sucked dust and air are sucked into theconnection opening 18 of the upper cover 16 through the extension pipe 4and the hose 2. The dust and air sucked into the connection opening 18are introduced into the dust collection case 19.

The air and the dust introduced into the dust collection case 19 flowsalong the peripheral wall of the dust collection case 19 as spiral flow,and the dust and the air are separated while flowing as the eddycurrents, and then the dust are accumulated on the bottom portion of thedust collection case 19. More specifically, the dust collection case 19comprises the function as the dust collection section for separatingdust from air and the function as a dust collection section foraccumulating the separated dust.

The separated air is sucked into the second and the third intake airpassages 24, 25 of the main body case 17 through the first intake airpassage 23 of the upper cover 16 from the upper side opening 19 a of thedust collection case 19; further the separated air is sucked into theintake vent 20 a of the motor fan 20.

The air sucked into the intake vent 20 a of the motor fan 20 isexhausted from the opening 27 a of the motor fan cover 27, and isexhausted to the outside from an exhaust vent (not shown) disposed inthe lateral of the rear wheel 12.

The outer wall of the battery 21 is covered by a cover (noise blockingmember) made of a material (for example, iron, aluminum, coal tar,rubber, and the like) which has a specific gravity larger than a resincomposing the main body case 17, so that the noise generated by therotation of fan effused from the intake vent 20 a of the motor fan 20can be effectively insulated and reduced.

Furthermore, although the battery cover 21 is covered by a cover havinga light specific gravity, the battery main body has a large specificgravity, and also has a sufficient thickness (a height in the up anddown direction in FIG. 1), such that the noise effused from the intakevent 20 a of the motor fan 20 is effectively blocked and reduced by thebattery 21. Accordingly, the noise leaked from the bottom of the vacuumcleaner main body 1 becomes small, and a silent electric vacuum cleanercan be obtained.

The air sucked into the first intake air passage 23 flows into theintake vent 20 a of the motor fan 20 along the lateral wall 14 d, sothat the battery 21 is cooled down through the lateral wall 14 d. Thetemperature of the air is low because of not cooling the motor fan 20,so that the battery 21 can be sufficiently cooled down. Further, thecooling efficiency can be improved by the contact between a part of thelateral wall 14 d and the outer surface 21 k of the battery 21.

The capacity flowing into the third intake air passage 25 is the samecapacity which sucks dust; accordingly, the lateral wall 14 d is cooleddown by a large capacity. Consequently, the battery 21 can besufficiently cooled down.

Further, the motor fan 20 is disposed with the state that one side ofthe motor fan is tilted to contact to the battery 21, enabling theheight of the vacuum cleaner main body 1 to be lowered, and the airpassage resistance to be small because the flowing direction of the airsucking from the third intake air passage 25 into the intake vent 20 aof the motor fan 20 does not change on a large scale.

The lateral wall 14 d may be separated from the upper case 14 composinga part of the main body case 17, and may be made of a material ormaterials (for example, duralumin, aluminum, iron, plumbum, and the likehaving larger thermal conductivity than a resin of the main body case17) having a specific gravity larger than a resin (for example ABS, PP,and the like) composing the main body case 17. The member (noiseblocking member) having a specific gravity larger than a resin composingthe main body case 17 is accordingly used, the site facing to the intakevent 20 a can effectively block (reduce) the noise generated by therotation of the fan driven by the motor fan 20. In this case, a thinsheet having a substantially 3 mm thickness is used for the material, sothat the thin sheet does not become a heavy material which has anegative influence on the total weight of the electric vacuum cleanermain body 1, enabling the noise to be insulated.

The cooling effect of the battery 21 can be further increased by havinga good thermal conductivity of the heavy member.

In the above embodiment, the motor fan 20 is tilted to be disposed; eventhough the intake vent 20 a is disposed downwardly without titling themotor fan 20, the noise of the fan can be certainly blocked and reducedbecause of placing the battery 21 in the position facing to the intakevent 20 a. Accordingly, the noise can not spread from the bottom surfaceof the vacuum cleaner main body 1 with a flooring material, and thelike, and a silent electric vacuum cleaner can be accomplished.

FIG. 3 illustrates the electric vacuum cleaner main body 1 of the secondembodiment. In the electric vacuum cleaner main body 1, an opening 14 eis formed on a lateral wall 14 d, an outer surface 21 k of a battery 21closes the opening 14 e and zones a third intake air passage 25, theouter surface 21 k of the battery 21 is cooled down by directly hittingthe air flowing into the third intake air passage 25 against the thirdintake air passage 25. More specifically, a part of the third intake airpassage 25 is configured by the battery 21, and the battery 21 isdirectly faced to an intake vent 20 a of a motor fan 20. By this way,the cooling efficiency of the battery 21 is further improved.

In this case, the opening 14 e of the lateral wall 14 d is also closedby the outer surface 21 k of the battery 21, and the noise of the fan ofthe motor fan 20 is blocked and reduced by the battery 21, so that thenoise leaked from the bottom of the vacuum cleaner main body 1 becomessmall as well as the first embodiment.

FIG. 4 illustrates the electronic vacuum cleaner of the thirdembodiment. In this third embodiment, one side surface 21 f of an outersurface 21 k of a battery unit 21 facing to an opening 14 e of a lateralwall 14 d is made of a metal (member having higher thermal conductivitythan resin of a main body case 17). The cooling efficiency of thebattery 21 is accordingly further improved. Furthermore, since noise isblocked and reduced by the metal (noise blocking member) of one sidesurface 21 f, the noise leaked from the bottom surface of the vacuumcleaner main body 1 can be further reduced. The metal may be applied toa part of the outer surface 21 k of the battery 21 facing to the opening14 e of the lateral wall 14 d.

EFFECT OF THE INVENTION

According to the present invention, the generation of noise of a motorfan can be reduced.

1. An electronic vacuum cleaner comprising: a main body case; an intakeair opening disposed in a front portion of the main body case; a dustseparation section which communicates with the intake air opening; amotor fan provided in a back portion of the main body case, an intakeair passage being provided from said dust separation section to saidmotor fan; and a noise blocking member which faces an intake vent of themotor fan with the intake air passage provided between the noiseblocking member and the intake vent; wherein the noise blocking memberhas a specific gravity that is larger than a specific gravity of amaterial composing said main body case; and wherein a surface of thenoise blocking member that faces the intake vent has an area that islarger than a project area of the intake vent, which is an area of theintake vent projected along a central axis of the intake vent on thesurface of the noise blocking member.
 2. The electric vacuum cleaneraccording to claim 1, wherein said noise blocking member comprises abattery for driving said motor fan.
 3. The electric vacuum cleaneraccording to claim 1, wherein said noise blocking member comprises apart of a wall surface of said intake air passage.
 4. The electricvacuum cleaner according to claim 3, wherein said wall surface with hasan opening, said noise blocking member comprises a battery for drivingsaid motor fan and faces the intake vent of said motor fan through theopening, and said opening is closed by a part of said battery.
 5. Anelectric vacuum cleaner comprising: a main body case; an intake airopening disposed in a front portion of the main body case; a dustseparation section which communicates with the intake air opening; amotor fan provided in a back portion of the main body case, an intakeair passage being provided from said dust separation section to saidmotor fan; and a battery which faces an intake vent of the motor fan viaa wall of the intake air passage such that the intake air passage isprovided between the noise blocking member and the intake vent; whereinthe battery has a specific gravity that is larger than a specificgravity of a material composing said main body case, and wherein asurface of the battery that faces the intake vent has an area that islarger than a project area of the intake vent, which is an area of theintake vent projected along a central axis of the intake vent on thesurface of the battery.
 6. The electric vacuum cleaner according toclaim 5, that wherein said wall portion comprises a material having athermal conductivity higher than the material composing said main bodycase, and said battery contacts the wall portion.
 7. The electric vacuumcleaner according to claim 1, wherein said noise blocking member ispositioned below said intake vent.
 8. An electric vacuum cleanercomprising: a main body case; an intake air opening disposed in a frontportion of the main body case; a dust separation section whichcommunicates with the intake air opening; a motor fan provided in a backportion of the main body case, an intake air passage being provided fromsaid dust separation section to said motor fan, and said motor fan beingtilted downwardly so that an intake vent of the motor fan is directedobliquely forward toward the front portion of the main body case andobliquely downward; and a battery, for driving the motor fan, positionedunder a bottom wall of a bottom portion of the intake air passage,wherein the bottom wall faces said intake vent.